Topic 63: Discuss the risks and challenges involved in working in a confined space.

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Confined space refers to an area which is enclosed with limited access that makes it dangerous to work. An example is the interior of a storage tank which workers may enter for maintenance work but which is not a habitable place.

Comments

Interesting topic! I have never considered the risks associated with this type of work. I think a major issue with working in confined spaces is not just the injuries that can be sustained whilst the task is underway, but also the recovery prospects of the individual should they become injured. This could arise from the ability of the individual concerned to communicate their injury back to their supervisor and be recovered quickly and also the accessibility of the confined space that they are in: how easy is it for them to be rescued? This issue can become particularly significant if the individual has become incapacitated, for example if they have passed out due to hypoxia, then they cannot communicate their injury and will need to be physically rescued.

When working in a confined space there are always risks
involved if due diligence and the correct assessment is carried out. Have to
work in a construed area does not mean the risk should be high but that one has
to be aware of the risk and prevent them before hand make sure you do not add
more clutter than you need only take what you need at one time. Even when
working with thing of flame have extinguishers around as chances of you
escaping are reduced. In having the correct working principals then working in
confined areas will not lead to high risk

I would like to add in this discussion that according to the legislation, either an employer or a self-employed person should conduct an assessment of the potential risks for the health and safety of those who will work in a confined place or for others that may be affected during the work, in order to recognize any measures that should be taken into account to meet the relevant regulations. This assessment should be reviewed frequently to be up to date with the current legislation while when a worker is going to be young person there should be considered some specific things like, lack of experience and awareness of risks, immature behaviour, training etc.

Having looked at the specific risks themselves, the majority stem from lack of ventilation in the area. This can lead to increased temperatures which can affect a worker's mentality and concentration. Also depending on the specific job, toxic gasses may tend to accumulate in the confined space, posing obvious health risks to any individuals exposed to them.
There is also a lack of fresh oxygen available to any workers within a confined space and the potential for them to inhale harmful levels of dust or other residues.

To add to Catriona and Michail’s comments on the topic - under law an employer is responsible for ensuring the safety of employees and others, and this is enforced by regulators. The Confined Spaces Regulations 1997 (found on HSE's website) offers some guidance to mitigating the risks associated with working in a confined space. Including:

Not to enter confined space unless absolutely necessary

Follow a safe system of work if entry to a confined space is unavoidable

Put in place adequate emergency arrangements before the start of work

Ultimately, I believe the employer is responsible for reducing the risks, and should provide the employee with the necessary items/equipment to be reasonably safe in an confined space. And should be held accountable if something were to happen to the employee.

I would like to add to Catriona's comments.Accumulated toxic gases in confined spaces is a major issue.So whenever a worker has to enter a confined space, first of all, the area inside should be checked with a gas monitor or sensor.It has to be done several times to ensure there is no toxic gas which could cause harm to the worker.The worker entering the confined space should be competent and be trained to do the job.The workers should work as a team.If a worker is inside the confined space, there should always be a "guard" outside. They should be able to communicate with each other. Ventilation and proper lighting should be provided.

Proper rescue operations should be in place incase of an emergency.Rescuers should be readily available and properly trained.The rescuers should also be protected against the cause of emergency.

Persons working in a confined space face risks of being suffocated, poisoned or drowned in a confined space such as a pipe, machinery room or a hole in the ground if appropriate rules are not followed.

In addition to those mentioned by Savitha, steps that can be taken before personnel enter a confined space are they ensure that:

They obtain a Permit to Work and a Confined Space Entry certificate

They have a competent and authorised standby person

A competent and authorised person must test the atmosphere to make sure it is breathable and safe

All physical isolations are in place

Steps usually taken during the work to ensure safe working include:

Test the atmosphere at all times

Keep a clear route to the exit

The standby person must:

Work only on this task

Stay close to the confined space entrance at all times

Be able to communicate with people inside the confined space and with key personnel at all times

As pointed out by Adejugba and others operations involving confined space are high risky as illustrated in the story below;

Working in a confined space is a very critical task with
high risk level and this can be illustrated in the story below;

On the 16th of August, 1989, three wielders were
asked to grid a valve wields inside a 45 feet long pipe. One of them decided to
go inside the pipe to do the grinding and suggested that he might have
breathing challenges while in the pipe thus, they agreed to feed in Oxygen from
the Oxyacetylene wielding cylinder via the gas hoses into the pipe as he climbed
into the pipe.

About 20 feet in the pipe he began the grinding operation
while the growing flammable Oxygen rich cloud found an ignition source via the sparks from
the grinding operation resulting explosion which burnt the wielder in the
confined space who later died in the hospital the next. So sad and painful a story!
With quilt, regrets and life stigma to live with as his colleagues reflects on
the incident.COULD THIS ACCIDENT HAVE BEEN AVOIDED????
Investigations revealed that the wielders observed the normal route for
wielding operation but here the environment CHANGED (CONFINED SPACE). The
answer is yes should the appropriate Job Safety Analysis (JSA) conducted and
approved prior to the operation in the confined space (inside the pipe). Job
Safety Analysis is a safety measure carried out to seek for inherent job
hazards and take actions on possible ways of handling or eliminate them as to
improve safety. This may be conducted prior to start of the job or conducted
throughout the project life cycle. Steps involved in JSA are;

oBreaking down the operation into smaller tasks

·Climbing into the pipe

·Grinding Process

·Climbing out of the pipe

oIdentifying inherent and potential hazards
related to the individual task

oDeveloping innovative plan to eliminate or
mitigate these hazards

·Climbing into the pipe: Check if the appropriate
confined space entry procedure is been followed

·Climbing out of the pipe: Ensure appropriate
attendant motoring and supervision in compliance with confined space exit.

JSA is very useful as it helps to improve safety and risk
management prior to working in confined space as well as a guide against future
reoccurrence and it must be sanctioned or conducted by a qualified safety
personnel who has highly knowledge of the given job tasks.

Agreeing with savitha's comment above, Because of the hazards associated with confine space proper risk assessment and gas testing must be carried out before a job. Will also like to add that if it is possible for any job to be done outside a confine space, then that option should be welcomed. But if not, systems such as the 'permit to work', LOTO(lock out tag out), Electrical isolation etc should be employed to mitigate these hazards associated with confine space.

A working space which is enclosed on both sides and has a reasonable risk of fire, explotion, asphyxiation or drowning is called a confined space. it may be small or restricted for workers to work freely. Haxards associated with confined space are reduced oxygen levels , risk of fire, noxious flumes, flooding etc.

Proper risk assessment should be done and the task should be well planned and organised. Each risk should be properly analyised and should find a way to overcome the risk. All emergency arrangements should be done. We should not allow others to enter the confined space unless it is safe, do not ignore any risk while working in a confined space, Dont work in a confined space unless it is essential.

To give an illustration to support the above discussion
on risk and challenges of working in a confined space.

According
to a report on EHS today website, “Engulfment takes the lives of three workers
in a trench collapse at a construction site. An employee dies instantly when a
spark causes an internal explosion; workers had failed to properly inspect the
tank he was cleaning for the presence of flammable materials. Fire-fighters are
trapped and critically injured when oxygen – displaced from a room where
ammonia was used in the manufacture of methamphetamine – sets up the perfect
storm for an explosion and subsequent building collapse “

Working in confined spaces presents new challenges,
professional advice and training should be taken when planning any work in a
confined space. Whether the result of human error, natural disaster or acts of
terrorism, the human toll of confined space emergencies can be devastatingnot only to rescue personnel, but also to
bystanders and co-workers who make valiant, and often futile, efforts to bring
victims to safety.

The key to safe and effective working in any
confined space is that you must ensure
the right preparation, training and rescue plan is formulated before workers
plan to work in a confined space.

Catriona is not the only one who has been in the dark concerning the issue of risks associated with working in confined spaces. I have never actually given thought to it. I commend Kevwe for raising the topic. Having read through various materials, I’ve found that working in confined spaces involves a lot of risk due to the presence of hazardous substances or conditions within the space. Also, looking at the topic statically, some of the statistics of fatalities recorded are astonishing. Between the five year period of 2005-2009, a total of 481 fatalities[1] was recorded in the US alone. Coming to the UK, though less staggering, a total of 15 deaths[2] is recorded every year. Principal causes of these accidents are due to Organisations failing to operate a “lessons learnt” approach from past accidents and Hazards not often reassessed[3]. To avoid incident or accident repetitions, I therefore suggest that organizations should incorporate a “what if” and “lessons learnt” approach in conducting rigorous risk/hazard reassessment before subjecting workers to a confined space.

Working in a confined space is encountered in various professions. Areas where entry and exits are limited and they are not designed for continuous employee occupancy like vessels, manholes, pipelines, vaults, tanks etc are categorized as confined spaces. Working in such an environment posses a lot of harm to the individual like the atmosphere in most confined spaces is oxygen deficient, combustible and toxic. Other forms of risk associated with working in a confined space have been mentioned in a previous post by Catriona. Dealing with this problem requires

•Identifying confined areas.
•Ensure personnel’s wear their appropriate Personal Protective Wear (PPE)
•An emergency response plan and personnel should be on standby during operations in the confined areas.
•Organizations should ensure they continuously inform and train personnel’s that are assigned to carry out operations that require them working in a confined space.

No matter the system of work in place, working in a confined space always presents an inherent risk. Therefore, it is always advisable to check if the work can be done in another way so that entry or work in confined spaces is avoided as better work-planning or a different approach can greatly reduce the need for ‘confined space’ work.

We should always try to analyse if the intended work is really necessary or if we could modify the confined space itself so that entry is not necessary or have the work done from outside (for example: blockages can be cleared in silos by use of remotely operated rotating flailed vices, inspection, sampling and cleaning operations can often be done from outside the space using appropriate equipment and tools and remote cameras can be used for internal inspection of vessels).

Complementing the discussion about the risks and challenges of working in confined spaces it would be worth to mention the main risks of working in confined spaces, also all aspects to be taken into account for the risk assessment and the mitigations to each risk to prepare a plan for these types of activities.

The main risks associated to confined space are:

Lack of oxygen

Toxic gas, fume or vapour

Dust

Previous contents, residues and contamination

Flammable substances or oxygen enrichment

Physical dimensions

Ingress or presence of liquids

Solid materials which can flow

Presence of excessive heat

Electricity or static electricity

Cleaning chemicals

Work out of hours.

Those risk would already be there or can be created while the activity is performed or as a result of performing it. Therefore a mitigation plan for working in confined spaces has to be developed based on a risk assessment and must consider: the type of task to be performed, the surrounded environment, communications e information of safe access and egress, mechanical and electrical isolation of equipment in the place, ventilation and purging ensuring oxygen levels are maintained and good working temperature, materials and tools to be used to avoid any sparks or potential fires, competency of personnel, adequate lighting without creating a source of ignition, and practical arrangements for rescue. This risk assessment and plan need to be well documented and discuss with personnel involved in the activity.

All those aspects are considered in the Confined Spaces Regulations 1997. Approved Code of Practice, Regulations and guidance.

I too have been looking at some real cases and statistics for confined space incidents. After reading some toe-curling stories about people suffocating in narrow pipes, I am surprised to read that approximately 2 thirds[1] of the fatalities are in fact people who are attempting to rescue those already stranded in a confined space. It would appear that when it comes to confined space safety, good entry practices are key. From the onset of a rescue, there is a narrow 4-minute window in which the casualty must be recovered before it is expected that they will not survive. The rescue procedure must therefore be meticulously planned and executed like clockwork. Rescuers will need to be given plenty training in administering oxygen or CPR and be ready to go at the drop of a hat.

Mostly specified risk in
confined spaces is due to fire or explosion in that confined space, unconsciousness
of the person due to increase of body temperature, toxic gas or fumes, lack of
oxygen in confined space.

I like to add some point with respect to the responsibilities of
the employer who carry work within confined space. According to Confined Space
Regulation 1997 to ensure the health and safety of the worker the employer
must Should conduct Risk Assessment, Conduct a risk assessment, Prevent
where possible the need to enter a confined space, Establish a Safe System of
Work, Provide adequate training and ensure that persons are competent to enter
the specific type of confined space in which they are to work, Provide the
correct type and quantity of PPE, Establish emergency procedures.

Many good points have been made. I'd say much more than confined spaces seen, it can also be created; This I mean going by the a space canbe made confined if not properly adressed. Confined Spaces can be as a result of Poor Plant and Equipment Layout.

Confined Spaces can be defined as an area where oxygen is irrespirable.

Challenges based on Confined Spaces can be handled through:

1) Examination and thorough consideration of all other alternatives which must give a sufficient reason for suck work.

2) An Emergency Response and REscue plan accompanied by a Trained and Experienced Rescue Team has been prepared, tested and put in place at the point that the work/job is performed.

3) A Safety Attendant must be on standby during the work to monitor the workers.

4) Atmospheric checks have been performed, as repeatedly as possible, to confirm and verify that there is no presence of such toxic gas elements.

5) Only trained workers should handle such jobs at confined spaces.

6) The Supervisor who signed the Job/Work order should endeavour to check to avoid errors.

7) Standard working procedures must be set out by companies/employers for such spaces.

Confined spaces are dangerous and could pose serious and even fatal injuries to workers. These spaces refers to enclosed area where with dangerous conditions which could result in injury or death for example storage tanks, silos, reaction vessels e.t.c.
Some of the dangers that may arise in confined spaces are:
I. Oxygen deprivation: workers are likely to experience an unexpected lack of oxygen when dealing with vessels that may be exposed to severe rust, or unfavourable reaction between elements present tin the enclosed region
II. Exposure to poisonous gases, vapours and fumes: considering the nature of the industry, oil and gas operations tend to deal with a lot of harmful chemicals and potentially toxic reactions. Although, the industry does all it can to limit exposure to such conditions, Workers working in confined spaces are at more risk in an instance of equipment malfunction.
III. Hot conditions which could rapidly increase body temperature
IV. Presence of dust in significantly high proportions which could choke workers
V. Fires and explosions
References:http://www.hse.gov.uk/pubns/indg258.pdf
Kuma Mede
51126022

A confined space is a work area where there is very limited access and limited supplies of fresh air

Working in confined area has a lots of hazards and an potential high risk of injury to those in the area. Confined areas are usually not designed as work areas. They have low ventilation around the area which allows hazardous atmospheres to develop quickly.

Hazards like : Serious injury arising through fire or explosion , Loss of consciousness through an increase in body temperature , Poor Ventilaition.

In the oil industry there are lots of confined spaces for work, it is a practice prior commencing the Job, a Proper risk analysis is done on the proposed work area by the HSE Rep, the analysis taken would be discussed with the workers before the job, a permit to work form must be taken and duly signed by the HSE manager , a rescue team must be close by, the exit area of the confined space is must be free., the personnel to enter this confined space needs to be competent for the task at hand. These mentioned practice would not total eliminate the risk involved but would reduce the impact of risk.

A confined space is never and would never be a comfortable work area for work, the key excellence in that area is carefulness and attention.

In order to manage and minimise risk exposure when working in confined spaces, It is paramount to thoroughly assess the risks working in confined regions could pose in order to produce adequate risk mitigation measures. Assessment should typically cover the following aspects
• The task
• The working environment
• Work materials and tools
• The suitability and competence of those carrying out the task
• Arrangements for emergency rescue
In cases where works assessment reveals high risks, it is always better to prevent entry into the confined space and carry out the task from outside. However, in situations where entry into the region is the only viable option, operators and personnel are advised to create a safe work system framework and provide emergency rescue arrangements before works commence.
References:http://www.hse.gov.uk/confinedspace/legislation.htm
Kuma Mede
51126022

During my industry experience I worked with a Squad in a confined space, as I have not undergone the training programme in order to safely work inside a confined space I was assigned the duty of ensuring the squad was safe within the confined space. I was given a radio for communication with the site office and safety officer if anything went wrong.
Before we could begin work we filled out a risk register as usual for any job on site. However as this was a confined space we also had to fill out a site specific confined space register and read over the companies safety manual in relation to confined spaces before we could begin.
Another safety method employed by this company was that the workers inside the confined space would hang up their ID badges outside to ensure it was known who was working inside.

The safety officer checked in with myself and my squad a number of times both in person and via the radio communication.
As mentioned before one can work in a confined space they must undergo a training programme to ensure they are aware of and know how to mitigate the risks associated with working in a confined space. This was show on the ID badges they displayed.

A brief look at some of the risks associated with working in a confined space are:

I can relate to your experience of confined spaces having worked in the construction industry for a number of years.

Confined space entry is a highly regulated activity both in the construction and the oil and gas industries.

Of course, as pointed out by my colleagues above, the first consideration when considering work within a confined space is wither or not it is needed at all. But there are times when working in a confined space is unavoidable.

In order to carry out work in a confined space, a thorough risk assessment is carried out. Control measures such as gas monitors, secondary means of escape and 15minute escape sets are needed. In all cases I have come across a permit to work system is used to manage confined space entry.

In my opinion confined space working can be made safe if the risk assessment is carried out and adhered to. Like most accidents it becomes dangerous when human behaviours are factored in.

A confined space without the correct controls in place can become a very dangerous environment. Hydrogen Sulphide, a toxic gas that is invisible and at high concentrations has no smell, is one of the hidden dangers.

So I guess that until we can find a different way to access underground pipes or store our fuel, confined spaces is something we will need to continue to manage

Elaborating on my previous comment and Haroons post, I would like to outline some practices that encompass creating a safe working system.
Creating a safe work system stems around utilizing the data obtained from the risk assessment that has been carried out and identifying precautions that could help reduce exposure to these identified risks. Fundamental risk mitigation measures aimed at creating safe work systems are outlined below as follows:
 Appointing a supervisor - supervisors have the responsibility of reviewing the operation at every stage and make sure necessary precautions are implemented.
 Ensure that the workers assigned to the task are suitable and competent - it is important to make sure workers have the training and experience required to complete the task. Assigning competent workers should is part of the supervisors responsibilities
 Isolation - ensure that electrical and mechanical equipment are isolated if they could be operated inadvertently. This limits the risks of fumes leaking or being liberated during the task. Furthermore, checks should be made regularly to ensure the isolation is effective and uncompromised
 Cleaning before entry - it is essential to make sure the space is thoroughly cleaned to prevent build up of fumes or other toxic substances.
 Check size of the entrance - ensure that entrance to the space is large enough to allow fully geared workers climb out easily
 Provision of ventilation - creating more openings could reduce the risk of oxygen deprivation. Furthermore, mechanical ventilation apparatus such as gas mask should be provided as an alternative source of fresh air.
 Testing the air - this is necessary to make sure the air is free from both toxic and flammable vapours and is clean enough for breathing. Ensure that testing is carried out by competent personnel.
 Provision of special tools and lighting - it is essential that non spark tools and protected lighting should be provide and utilised throughout the entire operation.
Despite and in addition to all these safety measures, it is remains important to setup emergency rescue operations.
References:http://www.hse.gov.uk/pubns/indg258.pdf
Kuma Mede
51126022

A best
example to show the difficulties in working a confined space is coal mines. The
risks associated with it is off the chart, if we look into the accidents
happened in coal mines most of them are by inhaling toxic gases, roof collapse,
explosion .etc.

When I was reading through
related confined space accidents, an incident came across. In that a 21 year
old tire repair technician who was repairing the inside of a truck tire with an
adhesive “Trichloroethylene” was killed by inhaling the toxic fumes
from the adhesive, here the victim was not provided with any safety measures by
the supervisor. The situation happened due to lack of knowledge in identifying
a confined space by the supervisors.

I realise that this topic in majority is relating to very
small confined spaces experience in many of our engineering backgrounds even in
the topic brief it states ‘Confined
space refers to an area which is enclosed with limited access that makes it
dangerous to work. An example is the interior of a storage tank which workers
may enter for maintenance work but which is not a habitable place'.

However I thought I would come in from a slightly different angle
and see what people thoughts are. If there is any such thing as an inhabitable
place it would be in the depths of the Ocean or in outer space. However in both
circumstance Humans have decided to travel and exist there for long periods of
time in the form of submarines and Space stations. Yes the living conditions on
both tend to be of a good quality and when it comes to risk they are maintained
to the highest level.

However it is not only physical risk which people may be at
risk of working in confined spaces. IN many submarines and definitely in space there
is of a small amount of people to interact with. There are long periods of time
where you will only communicate with those immediately around you, who in some
cases you may not get along with or just do not fulfil your needs. In situations
where it is a military submarine or you are limited to the amount of
communication to the outside world. There is in both circumstance a risk that someone
one struggles with adapting to their surrounds. Knowing they are trapped, and
that they only have what is around them to keep them occupied. It is not unknown
for this to cause workers to slightly lose their grasp on things/reality and
for them to suffer from the consequences. This is a challenge both workers and
employees have had to face, as the continued function and operation of the vessels
are dependent on the workers and without focused workers a small issue in these
inhabitable areas could lead to disastrous events.

Let me know what you think of my thoughts, have I missed the
point of this thread. Is mental issues as big a problem as physical issues?

I agree to
the views of Liam, if a small group of
people is working in a confined space the factors that can affect the group is
the mental and physical fitness of each individual. An error from an individual
can cause threat to the safety of his co workers. If we look in to the several
disasters happened in the coal mining industry, the careless behaviour of the
fellow worker had killed his co workers. This can be due to the explosions
caused by accident triggering of charges fixed in mines or similar events. So
training and guidance to the workers must be given by the supervisor regarding
the difficulties they have to face and how to resolve the associated risks in
that.

Working in a confined space as raised here is certainly hazardous. I want to analyse the risk involved in this operation from the perspective of emission, hence harmful gases like nitrogen, carbon IV oxide and others. Working in a confine space, in an event of an accidental discharge of these gases could result to a severe consequences on the personnel on duty as follows:

There would be somewhat breathing discomfort resulting from oxygen displacement in the area.

The impact of this on the workers ranges from loss of life, to choking of the breathing organs. For example, the effect of nitrongen gas discharge is commonly seen in the shipping yards. These gases are dangerous and therefore mitigating their impact will be to ensure that the working environment is properly ventilated to facilitate diffusion in an event of an accidentally discharge during operation.

Entering confined spaces which have or may have contained gas, liquid or solid products, presents risks
asphyxia, intoxication and explosion.

These risks are related to:

Equipment design: access, dimensions, internals, low points

Products contained: presence of deposits or mud, falls of internals due to corrosion

Clearing: blanketing followed by insufficient ventilation

Near environment: facilities or site machinery in service which can release noxious compounds
likely to enter the equipment.

However it's essential
that access to a confined space can be authorized only once the equipment has
been locked out. That is to say the
various phases of isolation have been performed such as separation, lock-out/isolation,
tag-out, purging: draining, washing, gas freeing, ventilation and gas test.

Authorization, proper supervision and control with adequate
measures are the only way safe working in confined space could be achieved.

A more technical analysis released by the Occupational Safety and Health Administration (OSHA) in January, 1993 described confined spaces to be areas large enough for an employee to eneter and work in, a space with limited or restricted access and not designed for continuous employee occupancy. According to OSHA statistics, asphyxiation is the number one cause of death in a confined space. In an effort to protect against this, best practices suggest that all confined spaces be evaluated prior to and continuously during entries with a calibrated, direct reading gas monitor containing the sensors such as oxygen, combustible gas, and any applicable toxic gas. Gases must be evaluated in four foot intervals in every direction of travel. Also employees with claustrophobic tendencies should be warned against working in such environment and subsequently excluded from such duties.References

when working in a confined space, the crew or members of crew are exposed to occurences as explotion, suffocation and indeed poison

in addition to those mentioned by olusola and savitha above, these some other task that must be carrried out to reduce the risk of the operation

A gas test should be conducted prior to begining to determine the type of gas present in the space and the adequate type of equipment that can be used to carry out the operation in the space.

if possible the area should be isolated, but if not the information on the nature of the operation been carried out must be communicated to every one in the area and if possible they should be included while carring out the risk assesment for the operation.

Confined space Operation has the major problem of limited amount of Oxygen and also visibility is also another challenging issue. There are standards in every country and companies required to be met before entering a confined space. Enterance into a confined space should always be seen as the last resort if every other thing has been tried to put things in order and it doesn't workout.

Before entering a confined space all safety rules must be adhered to and all necessary emergency measures put in place before the enterance of any worker.

The Atmosphere within and inside the confined space should be tested for Poisonous gases, which should be carried out by certified air quality professionals before the commencement of the Operation.

The enterance way should always be kept clear in the case an emergency it will be easier for the worker to escape.

CONCLUSION: The major Risks and challenges in a confined space operation are Oxygen supply, Space , Visibility etc.

Working in a confined space requires a team to be put in
place to serve as watch and in case of emergency d watch must not in any instant enter the environment
of the work. As this leads to fatalities in most cases and increase the number
of casualties.
The working space must also be clean and provision for must be made for oxygen
as this will help to sustain the personnel. Lighting of the environment is also
needed to help the workers have a good view of the work. Proper task risk
analysis must also be done before commencing the work.